Transcript for Hacker Found Dead Before Revealing Pacemaker Hacking Secrets

death of the computer hacker who warned implanted medical devices like pacemakers are vulnerable to fatal hack attacks. Linsey davis is here with more. Reporter: Something you'd see only in a suspense thriller. Hackers able to tinker with people's pacemakers sending a fatal electric shock to the life-saving devices and just to be clear, there are no indications that barney jack, the man who discovered this had a pacemaker but some find his death mysterious. His pacemaker can be wirelessly accessed with that number. Reporter: The shocking blot twist on the hit show "homeland." I'm killing you. Reporter: That scene got many wondering is it actually possible to hack implantable medical devices, specifically pacemakers. According to this man, the answer is yes. Professional hacker barnaby jack was set to reveal the secrets of just how it can be done this past weekend until he mysteriously turned up dead. Just days before the 35-year-old was to speak on hacking humans at a major las vegas hacking convention -- he was able to remotely exploit them and this talk was really dedicated to how the manufacturers could improve the security of the devices. discovered his body in his san FRANCISCO HOME ON JULY 25th. Now the coroner's office is trying to determine just how jack died. This morning, questions, even conspiracy theories are swirling all around the untimely death of the so-called ethical hacker who once wowed audiences with his demonstration of atm hacking. Jack dedicated his career to using his skills to expose vulnerabilities hackers can attack helping manufacturers develop tighter safety measures. He wanted to know how could that stuff down there fail and especially how could it fail if there were some not nice people out there trying to make it crash. Reporter: As for jack's warning, the fda says there is no calls for alarm for the nearly 3 million americans who have pacemakers saying it is not aware of any patient injuries or deaths associated with these incidents. Nor do we have any indication that any specific devices or systems in clinical use have been purposely targeted at this time. If you go to the dark side of this, it could unleash the ability, people to commit murder in effect to speed up pacemakers. Shut them down. Reporter: Meanwhile, some are now left wondering whether he could have been purposely targeted over his life's work. Advomed tells abc news no patient has ever been harmed as a result of either inadvertent or intentional cybersecurity measures. Police say there is no evidence of foul play and his sister releasing a statement overnight saying there has been overwhelming support from around the world for her brother.

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